Yields on U.S. government debt across all maturities have hit record lows in the post-AAA world as investors' enthusiasm for Treasuries intensified amid a tepid U.S. economic recovery, a growing European debt crisis and slowing growth in emerging markets, particularly China.

In recent weeks, the yield on the 10-year Treasury note has fallen to a record low below 1.4% from 2.6% a year ago. The 30-year yield has dropped to less than 2.5% from almost 4% last August. As investors buy Treasuries and drive up the price, yields decline.

"When there is a lot of turmoil and unease in financial markets, investors look for a safe haven," said David Coard, head of fixed income sales and trading at The Williams Capital Group. "Investors have said it all. In their minds, the U.S. is still worth a AAA rating and U.S. Treasuries continue to be the premier safe haven."

Central banks around the world have also helped push down Treasury rates. Since October, the Federal Reserve has been purchasing longer-dated Treasury bonds in an effort to keep long-term borrowing costs low for Americans and their businesses.

China and Japan, the two largest foreign holders of Treasuries, have also continued to buy up U.S. debt. China holds nearly $1.2 trillion of Treasuries, while Japan boasts $1.1 trillion, according to the latest Treasury International Capital report.

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Ever since the 2008 financial crisis rocked financial markets around the world, investors have been increasingly willing to accept even record low yields in return for the safety and liquidity of the $10.5 trillion Treasury market.

And that trend will likely continue.

"Right now we have a market that is being driven by fear," said Coard. "Because of Europe's debt crisis, investors will keep buying Treasuries to preserve their capital and rates will remain near record lows. They could even go lower if we get more bad news out of Europe."

A continued slowdown in China's growth momentum, further weakness in the U.S. economy and the failure of U.S. lawmakers to address the impending fiscal cliff could also push investors toward U.S. government debt, said Kim Rupert, fixed income analyst at Action Economics.

"The outcome of the combination of sequestration and expiration of the Bush era tax cuts will knock the United States into a recession," said Rupert. "Equities will tank, and investors will park more cash into Treasuries."

All in all, there aren't any looming catalysts that could push interest rates higher, said Bank of the West's Montaquila.

"There doesn't appear to be any inflation on the short-term horizon," he said. "The Fed has pledged to peg rates [to zero] through 2014. When you're operating under an environment like that, there's no real good reason for Treasury rates to go higher. "

Hibah Yousuf is a reporter at CNNMoney, where she covers stocks, bonds, commodities and currencies trading across the globe, as well as corporate earnings and other markets-related news. Prior to joining the site in 2009, she interned at Money Magazine.